Older adults with mild cognitive impairment (MCI) are the focus of intense interest in the scientific community. MCI patients demonstrate focal memory impairments that are not age expectable, and progress to clinically probable Alzheimer's disease (AD) at highly accelerated rates compared to cognitively normal peers. However, MCI patients also, by current definition, retain overall intact cognitive and everyday functional abilities and do not meet diagnostic criteria for AD. Thus MCI represents a pre-clinical phase of AD with important implications for early diagnosis and treatment. Currently MCI has been defined as a cognitive and specifically an amnestic syndrome. In contrast, the functional aspects and changes that occur in MCI are not well understood. This represents a fundamental knowledge gap for the field, in part because it is functional change in MCI that drives clinical judgments of conversion to AD. Understanding the nature, extent, and individual trajectories of functional change in MCI is essential to better characterization of this condition and to differentiation of normal aging, MCI and mild AD. For public policy reasons, it is also important to determine whether MCI patients are at risk for making poor financial, medical, and other decisions. In this five year study, we will systematically investigate functional change over time in MCI patients. Specifically, we will longitudinally investigate two higher order functional capacities: financial capacity (FC) and medical decision making capacity (MDC). FC and MDC are fundamental IADLs that are critical to independent functioning of older adults, very sensitive to mild dementia, and likely to show detectable and clinically meaningful changes in MCI. We will recruit and annually follow a baseline sample of 100 controls and 160 MCI patients, and also recruit a baseline only sample of 50 mild AD patients for cross-sectional comparison purposes. A multi-phased assessment of financial and medical capacity measures, self/informant report, and neurocognitive testing will be used to investigate FC and MDC in this sample. Cross-sectional, longitudinal, and cognitive predictor models of functional change in MCI will be developed and compared to the other groups. We hypothesize that MCI patients will demonstrate declines over time relative to controls in complex financial and treatment consent abilities, and that executive function and processing speed will be key neurocognitive mechanisms underlying these changes. For those MCI patients who convert to AD during the study, models of conversion combining functional and cognitive variables will be identified. This study will begin to address a key gap in the scientific and clinical understanding of MCI. [unreadable] [unreadable]